1. Field of the Invention
The present application relates to a transmitter optical module, in particular, a transmitter optical module having a plurality of optical signal sources.
2. Background Arts
An optical transmitter module that installs four laser diodes (herein after denoted as LDs) each emitting an optical beam with a specific wavelength different from others has been known in the field. In order to driver LDs installed within such a transmitter module, active devices, typically in integrated circuit (IC) implementing driver circuits to driver respective LDs, and passive devices of capacitors and inductors are inevitably installed within a housing of the transmitter module. In particular, when the operational speed of the LDs exceeds 10 Gbps, or reaches 25 Gbps, the assembly of such active and passive devices becomes a key factor for the transmitter module to show the designed performance. Moreover, recent trend for active optical components such an optical transceiver has continuously requested subjects inconsistent to each other, that is, the housing in the dimensions thereof is as small as possible, while, the performance or the operational speed thereof is as fast as possible.
In order to realize the operational speed exceeding 10 Gbps, the bonding wires connecting electrical components in the transmitter module should be short as possible. In other words, the electrical components are necessary to be positioned such that the bonding wires become shortest. A longer bonding wire causes an increase of the transmission impedance and degrades the high frequency performance of the transmitter module. The present application is to provide an arrangement of the components in the housing, by which the bonding wires effectively become shortest.